Apparatus including freezing unit and projector including freezing unit

ABSTRACT

There are disclosed an apparatus including a freezing unit capable of securely discharging drainage from an evaporator regardless of a posture change of a main body, and a projector including the freezing unit. A liquid crystal display projector (an apparatus) including a main body provided with a freezing unit having a refrigerant circuit constituted of at least a compressor, a radiator, a capillary tube (a pressure reducing unit) and an evaporator includes a tapered shape of a sealed path of a duct which surrounds the evaporator constituted in the whole region under the evaporator in a prospective posture change of the main body, a groove (a liquid receiving portion) formed in the center of the shape, and a wick (a discharge member) which discharges drainage received in this groove by use of a capillary force.

BACKGROUND OF THE INVENTION

The present invention relates to an apparatus in which a main bodyincludes a freezing unit having a refrigerant circuit constituted of acompressor, a radiator, a pressure reducing unit, an evaporator and thelike, and it also relates to a projector including the freezing unit.

Heretofore, a freezing unit having a refrigerant circuit constituted ofa compressor, a radiator, a pressure reducing unit, an evaporator andthe like is mounted on various apparatus such as a refrigerator, afreezer and an air conditioner. In the freezing unit, when thecompressor is driven, a refrigerant is sucked into a compression spaceand compressed therein to form a high-temperature high-pressurerefrigerant gas which flows into the radiator. The refrigerant which hasflowed into the radiator performs heat exchange between the refrigerantand surrounding air to radiate heat. Afterward, a pressure of therefrigerant is reduced in the pressure reducing unit, and therefrigerant reaches the evaporator.

Then, the refrigerant absorbs heat from the surrounding air to evaporatein the evaporator, and is then sucked into the compressor again, andthis cycle is repeated. Moreover, in the evaporator, the heat exchangebetween the evaporator and the refrigerant is performed, whereby a watercontent included in the air is condensed on the surface of theevaporator, and drops down as water droplets. To solve the problem, atray is installed in a lower part of the evaporator so that drainage(condensed water) from the evaporator can be received in this tray.Then, the drainage which has dropped down to the tray is then dischargedfrom the freezing unit via a pipe connected to a bottom part of the tray(e.g., Japanese Patent Application Laid-Open No. 2001-99558).

In addition, the applicant has previously developed a projectorincluding this freezing unit mounted thereon so that an optical elementof the projector is cooled in the cold air through the evaporator. Theoptical element of the projector is cooled in the freezing unit in thismanner, whereby a temperature of the optical element can be held at asuitable temperature. Moreover, various effects such as reducing ofamount of air flows, improvement of an energy efficiency and reducing ofan installation space can be obtained.

On the other hand, such a projector is provided so that the main body isrotatable around a burner axis (an optical axis) of a light source lamp,and hence the freezing unit needs to be provided in accordance with thisconstitution. In this case, the drainage from the evaporator drops downto any place owing to the rotation of the projector. Therefore, when thetray is only installed in the lower part of the evaporator as in theconventional example, with all prospective postures of the main body,the drainage from the evaporator cannot be received and discharged fromthe projector.

SUMMARY OF THE INVENTION

The present invention has been developed in order to solve aconventional technical problem, and an object thereof is to provide anapparatus including a freezing unit capable of securely dischargingdrainage from an evaporator regardless of a posture change of a mainbody, and a projector including the freezing unit.

An apparatus including a freezing unit according to a first aspect ofthe invention is an apparatus in which a main body is provided with thefreezing unit having a refrigerant circuit constituted of at least acompressor, a radiator, a pressure reducing unit and an evaporator,characterized by comprising: a liquid receiving portion constituted inthe whole region under the evaporator in a prospective posture change ofthe main body; and a discharge member which discharges drainage receivedin this liquid receiving portion by use of a capillary force or apermeation force.

An apparatus including the freezing unit according to a second aspect ofthe invention is characterized in that in the first aspect of theinvention, the discharge member discharges, to the radiator, thedrainage received in the liquid receiving portion.

A projector including a freezing unit according to a third aspect of theinvention which is the apparatus according to the above inventions,characterized by comprising a main body including a light source, anoptical element which processes light emitted from this light source inaccordance with image information, a projection lens which projects aprojected image of the processed light onto a screen, and a duct inwhich an evaporator is incorporated and which supplies, to the opticalelement, air subjected to heat exchange between the air and theevaporator, wherein the liquid receiving portion is constituted in aninner surface of the duct.

According to the first aspect of the invention, the apparatus in whichthe main body is provided with the freezing unit having the refrigerantcircuit constituted of at least the compressor, the radiator, thepressure reducing unit and the evaporator comprises the liquid receivingportion constituted in the whole region under the evaporator in theprospective posture change of the main body, and the discharge memberwhich discharges the drainage received in this liquid receiving portionby use of the capillary force or the permeation force. Therefore, evenwhen the posture of the main body changes, the drainage from theevaporator can be received by the liquid receiving portion, and can bedescribed from the apparatus by the discharge member.

In particular, as in the second aspect of the invention, the dischargemember discharges, to the radiator, the drainage received in the liquidreceiving portion, so that the drainage can be evaporated by radiantheat of the radiator.

Furthermore, as in the third aspect of the invention, the projector isthe apparatus according to the first or second aspect of the invention,the main body of the projector includes the light source, the opticalelement which processes the light emitted from this light source inaccordance with the image information, the projection lens whichprojects the projection image of the processed light onto the screen,and the duct in which the evaporator is incorporated and which supplies,to the optical element, the air subjected to the heat exchange betweenthe air and the evaporator, and the liquid receiving portion isconstituted in the duct inner surface. In consequence, even when thefreezing unit is mounted on the projector, the drainage from theevaporator can be discharged from a duct, and hence a disadvantage thatthe drainage flows through the optical element can be avoided inadvance.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view showing a schematic constitution of aliquid crystal display projector as one embodiment of an apparatusincluding a freezing unit to which the present invention is applied;

FIG. 2 is an arrangement diagram viewed from a front surface of thefreezing unit of the liquid crystal display projector shown in FIG. 1;

FIG. 3 is an arrangement diagram viewed from one side surface of thefreezing unit of the liquid crystal display projector shown in FIG. 1;

FIG. 4 is an arrangement diagram viewed from a plane of the freezingunit of the liquid crystal display projector shown in FIG. 1;

FIG. 5 is a diagram showing a duct of the liquid crystal displayprojector shown in FIG. 1, and flow of air flowing through the duct; and

FIG. 6 is a diagram showing the freezing unit in a case where a mainbody of the projector shown in FIG. 1 rotates.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

An embodiment of the present invention will hereinafter be described indetail with reference to the drawings. FIG. 1 is a schematic perspectiveview showing a projector as one embodiment of an apparatus including afreezing unit according to the present invention. The projectoraccording to the present embodiment is a liquid crystal displayprojector P constituted by providing, in a main body 1, a light source2, an optical path changing member 3, a uniform illumination opticalsystem (not shown), a color separation optical system (not shown), anoptical element 5, a projection lens 9 and a freezing unit 10 of theoptical element 5. The main body 1 is a flat housing constituted of amaterial having an excellent heat release property, for example,magnesium. It is to be noted that for the sake of description of eachunit provided in the main body 1, the main body 1 is shown in a flatsection in which an upper part of the main body is cut.

The light source 2 includes a lamp 20 such as an extra-high pressuremercury lamp, and a reflector 21 for emitting forwards light (divergentlight) diverging from the lamp. In the light source 2 of the embodiment,a plurality of (four) lamps 20 are provided with the reflectors 21,respectively, and the light source is received in lamp boxes 22 providedin the main body 1.

The uniform illumination optical system converts the light emitted fromthe light source 2 into a parallel luminous flux having a uniformluminance distribution, and includes an integrator lens, a condenserlens and the like. Moreover, the color separation optical systemseparates the parallel luminous flux from the uniform illuminationoptical system into light of colors R, G and B, and includes a dichroicmirror (not shown) and a mirror 4 for reflection (not shown in FIG. 1,and shown in FIG. 4 as described later) which separates the parallelluminous flux from the uniform illumination optical system into therespective colors and the like.

As shown in FIG. 4 or 5, the optical element 5 includes three liquidcrystal display panels (LCD panels) 6, incident-side sheet polarizers 8Aeach disposed with a space from each liquid crystal panel 6 on anincidence side of the panel, outgoing-side sheet polarizers 8B (shown inFIGS. 4 and 5 as described later) each disposed with a space from eachliquid crystal panel 6 on an emission side, a cross dichroic prism 25and the like. The liquid crystal display panels 6 process (modulate)light separated by the color separation optical system and guided to theliquid crystal display panels 6 in accordance with image information.The cross dichroic prism 25 synthesizes each color light to form aprojected light image. This cross dichroic prism 25 includes areflective surface including X-like dielectric multilayer films, and thelight from each liquid crystal panel 6 is formed into a single luminousflux via the reflective surface. It is to be noted that the projectionlens 9 enlarges and projects the projected light image from the crossdichroic prism 25 onto the screen, and is detachably attached to a hole(not shown) formed in a wall surface of the main body 1. Further in FIG.1, reference numeral 27 is a box member which covers an optical path forguiding the light emitted from the light source 2 to the liquid crystaldisplay panels 6, the incident-side sheet polarizers 8A, 8B and thelike, it is a leg portion provided on a bottom part of the main body 1,and 18M is a motor of a fan 18F described later. That is, a path (anoptical path) through which the light passes from the light source 2 tothe incident-side sheet polarizers 8A on the incidence side of theliquid crystal display panels 6 is formed in the box member 27.

An operation of the above constitution will be described. The lightemitted from the light source 2 is converted into the parallel luminousfluxes having a uniform luminance distribution via the uniformillumination optical system, separated into the light of the colors R, Gand B in the color separation optical system, and guided into the liquidcrystal display panels 6 which function as corresponding light bulbs viathe incidence-side incident-side sheet polarizers 8A. The luminousfluxes guided into the liquid crystal display panels 6 are modulated inaccordance with the image information in the panels, converted into aprojected image of the single luminous flux by the cross dichroic prism25 through the emission-side outgoing-side sheet polarizers 8B, andenlarged and projected on the screen by the projection lens 9.

Next, a freezing unit 10 of the present invention will be described withreference to FIGS. 2 to 4. FIGS. 2 to 4 are diagrams showingarrangements of the freezing unit 10 of the present invention as viewedfrom a front surface (a projection lens 9 side), a side surface and aplane. The liquid crystal display projector P of the present inventionincludes the freezing unit 10 in the main body 1. This freezing unit 10cools the optical element 5 including the liquid crystal display panels6, the incident-side sheet polarizers 8A, 8B, the cross dichroic crossdichroic prism 25 and the like, and is constituted of a compressor 12, aradiator 14, a capillary tube 16 (a pressure reducing unit of thepresent invention) and an evaporator 18 as shown in FIGS. 2 to 4. Thatis, a refrigerant discharge tube 13 of the compressor 12 is connected toan inlet of the radiator 14, and an outlet of the radiator 14 isconnected to a refrigerant pipe 15 extending to the capillary tube 16.An outlet of the capillary tube. 16 is connected to an inlet of theevaporator 18 via a refrigerant pipe 17 (an inlet pipe of the evaporator18), and an outlet of the evaporator 18 is connected to a refrigerantsuction tube 11 (an outlet pipe of the evaporator 18) of the compressor12 to constitute an annular refrigerant circuit.

The compressor 12 of the present embodiment is constituted by disposing,in a sealed container 12A having a vertically long cylindrical shape, acompression element and an electromotive element (a driving element) fordriving this compression element. The radiator 14 for use in theembodiment is a heat exchanger of an air cooling type, and hence a fan14F as blowing means is installed in the vicinity of (on the side of)the radiator 14. It is to be noted that in the present embodiment, thecapillary tube 16 is used as a unit to reduce a pressure of therefrigerant, but the pressure reducing unit is not limited to thecapillary tube, and any type of unit, for example, an expansion valvemay be used as long as the pressure of the refrigerant can be reduced toa predetermined pressure.

The freezing unit 10 is constituted so that a basic posture thereof canbe maintained in accordance with a posture change of the main body 1 ofthe liquid crystal display projector P by posture adjustment means. Inthe present embodiment, the basic posture is such a posture of thefreezing unit 10 that oil can smoothly be supplied to a frictionalportion (a sliding portion) of the compressor 12 (a lubricatingcharacteristic is satisfactory) and that reliability of flow of therefrigerant in the refrigerant circuit is satisfactory. The postureadjustment means of the present embodiment is constituted of abasket-like rotator 40, and the freezing unit 10 is installed rotatablyaround a rotary shaft B disposed in parallel with a burner axis A (anoptical axis) of the light source 2 on the same plane. Specifically, inthis rotator 40, the compressor 12, the radiator 14 and the fan 14F ofthe radiator 14 are received, and the evaporator 18 is disposed in aduct 50 described later. The capillary tube 16 is disposed in a spacebetween the rotator 40 and the duct 50.

An outer side surface of the rotator 40 is a disc-like panel 42, andthis panel is rotatably disposed in a circular hole 43 formed in a sidewall 1A of the main body 1 of the liquid crystal display projector P.That is, the rotator 40 of the present embodiment is rotatably supportedon the side wall 1A of the main body 1 by the hole 43 of the main body1. The panel surface 42 exposed to the outer surface of the main body 1is provided with a dial 45 for adjusting a position of the rotator 40.That is, the rotator 40 of the present embodiment is constituted so thatthe dial 45 can be operated to adjust the posture of the rotator 40. Itis to be noted that in the present embodiment, the dial 45 is operatedto adjust the posture of the rotator 40, and the basic posture of thefreezing unit 10 is maintained. However, for example, the posture of therotator 40 may automatically be adjusted in accordance with a gravityand a gravity center position, or the posture of the freezing unit 10may automatically be adjusted with a posture sensor, an encoder or thelike.

Then, in the rotator 40, the compressor 12, the radiator 14 and the fan14F are arranged around the rotary shaft B of the rotator 40.Specifically, the compressor 12, the fan 14F and the radiator 14 arearranged in order of the compressor 12, the fan 14F and the radiator 14in a diametric direction of the rotator 40 crossing an axial centerdirection of the rotary shaft B at right angles, and they are arrangedin parallel on the same plane. That is, as shown in FIG. 3, thecompressor 12 is disposed along one side surface of the fan 14F, and theradiator 14 is disposed along the other side surface of the fan 14F. Inparticular, according to the present embodiment, in a positioncorresponding to the rotation center of the rotator 40, the compressor12 is disposed in the rotator 40 with the basic posture in a positionwhere a vertically long cylindrical axis (a vertical axis) of thecompressor 12 crosses the rotary shaft B of the rotator 40 at rightangles.

Moreover, the capillary tube 16 and the evaporator 18 are similarlyarranged around the rotary shaft B of the rotator 40. In the presentembodiment, the capillary tube 16 and the evaporator 18 are positionedlinearly with the units (the rotator 40, the fan 14F and the radiator14) arranged in the diametric direction crossing the axial centerdirection at right angles in the rotator 40.

The compressor 12, the radiator 14 and the evaporator 18 are arrangedaround the rotary shaft B in this manner, whereby the freezing unit 10can smoothly be rotated by the rotator 40. Especially, the unitsconstituting the freezing unit 10 (the compressor 12, the radiator 14,the fan 14F, the capillary tube 16 and the evaporator 18) are linearlyarranged, and a diameter of the freezing unit 10 rotated by the rotator40 is set to be smaller than that of the rotator 40, whereby thefreezing unit 10 can be received in a diametric region of the rotator40. Therefore, a rotation radius of the freezing unit 10 can be reduced,smoother rotation can be achieved owing to the rotator 40, and excessiveenlargement of the rotator 40 can be prevented.

On the other hand, the duct 50 is disposed around the optical element 5including the liquid crystal display panels 6, the incident-side sheetpolarizers 8A, 8B, the cross dichroic cross dichroic prism 25 and thelike, and cold air subjected to the heat exchange between the air andthe evaporator 18 is supplied to the optical element 5 including theliquid crystal display panels 6, the incident-side sheet polarizers 8A,8B, the cross dichroic prism 25 and the like via the duct 50. That is,in the liquid crystal display projector P of the present embodiment, theoptical element 5 is disposed in a cooling air path constituted of theduct 50 having a semi-sealed structure, and the optical element islocally cooled by the cold air circulated through the duct 50.

This duct 50 is constituted of an insulating material. Examples of theusable insulating material include rubber/plastic materials such as hardchloride vinyl, a silicon resin, a fluorine resin, a phenol resin, apolycarbonate resin and a polystyrene resin having a thermalconductivity of about 0.1 W/(m·K) to 0.3 W/(m·K), glass materials suchas quartz glass and glass ceramic having a thermal conductivity of about1 W/(m·K) to 4 W/(m·K), fiber insulating materials such as glass wool,rock wool and carbide cork having a thermal conductivity of about 0.0045W/(m·K) or less, foam styrol, and insulating materials for constructionand vacuum insulating materials constituted of these materials. Inaddition, as the insulating material, a material having a thermalconductivity of 1 W/(m·K) or less may be used.

Moreover, as described above, the evaporator 18 of the freezing unit 10is incorporated in the duct 50, and the cold air subjected to the heatexchange between the air and the evaporator 18 can be circulated andsupplied to the optical element. As shown in FIG. 5, the duct 50 isformed around the liquid crystal display panels 6 and the cross dichroicprism 25, and is constituted of a sealed path 50A having a substantiallyU-shape, and communication tubes 50B which connect blowout ports 52formed in one end of the sealed path 50A positioned above the liquidcrystal display panels 6 and suction ports 53 formed in the other end ofthe sealed path 50A positioned under the liquid crystal display panels6. In the sealed path 50A, the evaporator 18 and the fan 18F arearranged.

Furthermore, in the communication tubes 50B, the liquid crystal displaypanels 6 (one of the three liquid crystal display panels 6 is installedin one communication tube 50B) and the incident-side sheet polarizers8A, 8B are installed. Each liquid crystal panel 6 and the incident-sidesheet polarizers 8A, 8B are arranged with a space therebetween in thecommunication tube 50B. The polarization plate 8A is disposed with aspace from one wall surface of the communication tube 50B, and thepolarization plate 8B is similarly disposed with a space from the otherwall surface of the communication tube 50B. Furthermore, thecommunication tubes 50B are constituted so that the liquid crystaldisplay panels 6, the incident-side sheet polarizers 8A, 8B, light to beradiated, and the image information modulated by the liquid crystaldisplay panels 6 and then sent to the cross dichroic prism 25 are notdisturbed and that the cold air subjected to the heat exchange betweenthe air and the evaporator 18 are supplied to the liquid crystal displaypanels 6, the incident-side sheet polarizers 8A, 8B and the crossdichroic prism 25.

The evaporator 18 incorporated in this duct 50 is connected to therefrigerant pipe 17 from the capillary tube 16 on an inlet side, andconnected to the refrigerant suction tube 11 of the compressor 12 on anoutlet side. IN the present embodiment, the evaporator 18 is disposedrotatably by the rotator 40 in the duct 50. That is, a hole 19 extendingthrough the duct 50 is formed in a side wall of the sealed path 50A ofthe duct 50 corresponding to the rotary shaft B of the rotator 40, andthe refrigerant pipe 17 and the refrigerant suction tube 11 are arrangedapart from each other along the rotary shaft B of the rotator 40 in aninsulating manner.

Thus, the refrigerant pipe 17 connected to the inlet side of theevaporator 18 and the refrigerant suction tube 11 connected to theoutlet side of the evaporator 18 are arranged along the rotary shaft Bof the rotator 40, whereby the evaporator 18 can be disposed rotatablyby the rotator 40 in the duct 50. Furthermore, the refrigerant pipe 17and the refrigerant suction tube 11 are arranged apart from each otherin the insulating manner, whereby it is possible to prevent adisadvantage that the refrigerant flowing through the refrigerant pipe17 extending from the capillary tube 16 to the evaporator 18 and therefrigerant flowing through the refrigerant suction tube 11 extendingfrom the evaporator 18 to the compressor 12 perform heat exchangetherebetween. That is, the refrigerant having the pressure thereofreduced by the capillary tube 16 absorbs heat from the refrigerantflowing through the refrigerant suction tube 11 to evaporate, whereby itis possible to eliminate a disadvantage that a heat absorbing functionin the evaporator 18 lowers and that the air circulated through theevaporator 18 is not easily cooled.

A cooling operation of the liquid crystal display panels 6 having theabove constitution according to the present embodiment will bedescribed. When the compressor 12 in the rotator 40 is driven, alow-temperature low-pressure refrigerant is sucked from the refrigerantsuction tube 11 into a compression element (not shown), and compressedin the element. The compressed high-temperature high-pressurerefrigerant is discharged to the refrigerant discharge tube 13, andflows into the radiator 14. The refrigerant which has flowed into theradiator 14 performs heat exchange between the refrigerant and the airblown by the fan 14F in the radiator to radiate heat. The refrigerantwhich has radiated the heat in the radiator 14 enters the capillary tube16 disposed between the rotator 40 and the duct 50 through therefrigerant pipe 15. While the refrigerant passes through the capillarytube 16, the pressure thereof is reduced. In this state, the refrigerantflows into the evaporator 18 in the duct 50 through the refrigerant pipe17. It is to be noted that the refrigerant pipe 17 is disposed apartfrom the refrigerant suction tube 11 connected to the outlet side of theevaporator 18 in the insulating manner as described above, so that therefrigerant flowing through the refrigerant pipe 17 as described aboveis not influenced by the refrigerant flowing through the refrigerantsuction tube 11, that is, the refrigerant does not absorb any heat fromthe refrigerant flowing through the refrigerant suction tube 11, doesnot evaporate, and flows into the evaporator 18.

The refrigerant which has flowed into the evaporator 18 takes the heatfrom the air circulated through the duct 50 to evaporate in theevaporator. Then, the refrigerant which has received the heat (i.e., theheat of the optical element 5) of the air circulated through the duct 50flows into the refrigerant suction tube 11, flows from the duct 50 viathe hole 19, is sucked into the reflector 21 disposed in the rotator 40,is compressed, flows into the radiator 14, and releases the heat to theair blown in the radiator 14. Thus, the refrigerant repeats this cycle.

On the other hand, the air cooled by taking the heat from the air by therefrigerant in the evaporator 18 is discharged into the communicationtube 50B from the blowout ports 52 formed right above the liquid crystaldisplay panels 6 and the incident-side sheet polarizers BA, 8B by thefan 18F installed in the sealed path 50A of the duct 50, and supplied tothe liquid crystal display panels 6, the incident-side sheet polarizers8A, 8B and the cross dichroic prism 25. That is, the air which has flowsinto the communication tube 50B from the blowout ports 52 passes throughgaps formed between the liquid crystal display panels 6 and theincident-side sheet polarizers 8A provided in the communication tubes50B, between the liquid crystal display panels 6 and the outgoing-sidesheet polarizers 8B, between the polarization plate 8A and one wallsurface of the communication tube 50B (i.e., a hole connected to anopening of the box member 27) and between the polarization plate 8B andthe other wall surface of the communication tube 50B (i.e., the crossdichroic prism 25). In consequence, the liquid crystal display panels 6,the incident-side sheet polarizers 8A, 8B and the cross dichroic prism25 release the heat to the air (cold air), and are cooled.

Then, the air heated by receiving the heat from the liquid crystaldisplay panels 6, the incident-side sheet polarizers 8A, 8B and thecross dichroic prism 25 is sucked into the sealed path 50A from thesuction ports 53 formed right under the liquid crystal display panels 6and the incident-side sheet polarizers 8A, 8B to reach the evaporator18. In the evaporator, the air is cooled by the heat exchange performedbetween the air and the refrigerant flowing through the evaporator 18,and is supplied to the liquid crystal display panels 6, theincident-side sheet polarizers 8A, 8B and the cross dichroic prism 25from the blowout ports 52 via the fan 18F again, thereby repeating thecycle.

Thus, the duct 50 for supplying the cold air subjected to the heatexchange between the air and the evaporator 18 of the freezing unit 10to the liquid crystal display panels 6, the incident-side sheetpolarizers 8A, 8B and the cross dichroic prism 25-is formed around theliquid crystal display panels 6, the incident-side sheet polarizers 8A,8B and the cross dichroic prism 25, whereby the air subjected to theheat exchange between the air and the evaporator 18 of the freezing unit10 can be supplied to the liquid crystal display panels 6, theincident-side sheet polarizers 8A, 8B, the cross dichroic prism 25 andthe like and can be cooled by the fan 18F. In consequence, the liquidcrystal display panels 6, the incident-side sheet polarizers 8A, 8B, thecross dichroic prism 25 and the like can be cooled without beinginfluenced by an outside air temperature, and the optical element 5including the liquid crystal display panels 6, the incident-side sheetpolarizers 8A, 8B, the cross dichroic prism 25 and the like canconstantly be maintained at an optimum constant temperature.

In particular, the cold air subjected to the heat exchange between theair and the evaporator 18 can constantly be supplied to the liquidcrystal display panels 6, the incident-side sheet polarizers 8A, 8B andthe cross dichroic prism 25 as described above, so that an amount of theheat to be released is remarkably increased as compared with a casewhere outside air is supplied to the liquid crystal display projectorsas in a conventional example. Therefore, the fan is miniaturized toreduce an installation space, and an amount of the air to be blown bythe fan can be reduced to reduce noise. Furthermore, as compared withconventional electronic cooling, an energy efficiency can remarkably beimproved.

Furthermore, the air heated by the heat generated by the liquid crystaldisplay panels 6 and the refrigerant flowing through the evaporator 18of the freezing unit 10 perform heat exchange therebetween, whereby theheat of the liquid crystal display panels 6 can be conveyed by therefrigerant, and released to the outside air blown in the radiator 14.Therefore, unlike a case where the optical element is cooled by theelectronic cooling, a degree of freedom in spatial layout design (in themain body 1) improves.

On the other hand, in a case where the liquid crystal display projectorP is rotated around the burner axis A of the light source 2 as describedabove, the dial 45 attached to the panel 42 on the side of the outersurface of the rotator 40 is operated, whereby the freezing unit 10 canmaintain its basic posture as shown in FIG. 6.

Thus, when the main body 1 rotates, the dial 45 is operated to adjustthe posture of the freezing unit 10. In consequence, even when the mainbody 1 rotates to any posture, for example, even when the main body 1 isvertically (head and tail) reversed around the burner axis A of thelight source 2, the basic posture of the freezing unit 10 can bemaintained, so that the freezing unit 10 can be operated without anytrouble. In consequence, without constituting any special oil supplymechanism in the compressor 12, the oil can smoothly be supplied to africtional part, so that enlargement of the compressor 12 and steep riseof manufacturing cost can be minimized.

In addition, as described above, the air circulated through the duct 50performs heat exchange between the air and the refrigerant, and iscooled in the evaporator 18, whereby a water content in the air iscondensed on the surface of the evaporator 18, and then drops down aswater droplets. In a case where the evaporator 18 is installed in theduct 50 having a semi-sealed structure as in the present embodiment,about several grams of water content is collected from the circulatedair at a time when the liquid crystal display projector P is used once.

With regard to drainage (condensed water) from this evaporator. 18, in acase where the freezing unit is installed in a stationary apparatus,that is, an apparatus which does not rotate or tilt as in a conventionalfreezing unit, a tray for receiving the drainage is installed in a lowerpart of the evaporator, and a pipe for discharging the drainage whichhas dropped down to the tray is attached to a bottom part of the tray,whereby the drainage from the evaporator is received in the tray.Afterward, the drainage can be discharged from the pipe connected to thebottom part of the tray. However, in a case where the freezing unit ismounted on an apparatus such as the liquid crystal display projector Pin which the posture of the main body 1 changes (rotates), a placecorresponding to the lower part of the evaporator 18 differs for eachposture of the main body 1, so that even when the tray is disposed as inthe conventional example, it is difficult to receive and discharge thedrainage from the evaporator 18.

In this case, the drainage from the evaporator 18 scatters in the duct50. In the worst case, together with the circulated air, the drainageflows into the communication tubes 50B from the blowout ports 52, orflows into the communication tubes 50B from the discharge ports 53 toinvade the optical elements 5 provided in the tubes including the liquidcrystal display panels 6, the incident-side sheet polarizers 8A, 8B andthe like, whereby the optical element 5 might be damaged, and theprocessing of the light emitted from the light source might bedisturbed.

To solve the problem, in the liquid crystal display projector P of thepresent invention, a liquid receiving portion is constituted in thewhole region under the evaporator 18 in the prospective posture changeof the main body 1. This liquid receiving portion is constituted in theinner surface of the duct 50. As shown in FIG. 1, the liquid receivingportion of the present embodiment is constituted of a tapered shapehaving the center thereof outside and a grove 70 formed in the center ofthe shape in the whole inner surface of the sealed path 50A of the duct50 which surrounds the evaporator 18, so that the drainage from theevaporator 18 can be collected in the grove 70.

Furthermore, the projector is provided with a discharge member whichdischarges the drainage received in the grove 70 by use of a capillaryforce or a permeation force. As the discharge member made of a metal,for example, a wick is used. Typical examples of the member include agroove along an inner diameter of a metal pipe, a sintered metal, ametal mesh, and a plurality of fine wires. As a fibrous material, forexample, sponge, thread or the like may be used in the presentembodiment, the discharge member is constituted of a wick 75, and oneend of this wick 75 opens in the grove 70 provided in the duct 50. Then,this wick 75 extends externally from the duct 50 via one open end of thewick in the grove 70 to enter the rotator 40. The other end of the wickabuts on the radiator 14 to open, or opens in the vicinity of theradiator 14. In the present embodiment, the one end of the wick 75 isattached to one end of the main body 1 on the side of a bottom surface.The wick 75 has a sufficient length or is constituted of a flexiblematerial so that a connected state can be maintained even in a casewhere the rotator 40 rotates.

In such a constitution, in a case where the liquid crystal displayprojector P is rotated around the burner axis A of the light source 2 asdescribed above, the drainage which has dropped down from the evaporator18 drops down to the inner surface of the sealed path 50A of the duct 50disposed on the downside owing to the posture of the main body 1, andthe drainage is received in the grove 70 formed in the center owing tothe tapered shape of the sealed path 50A. Then, the drainage in thegrove 70 enters the wick 75 from one end which opens in the grove 70,and is discharged from the duct 50 to the radiator 14 owing to thecapillary force of the wick.

Moreover, the drainage discharged to the radiator 14 is heated by theradiant heat of the refrigerant flowing through the radiator 14 toevaporate. Thus, the opening of the other end of the wick 75 is disposedso as to abut on the radiator 14, or is disposed in the vicinity of theradiator 14, whereby the drainage from the evaporator 18 can beevaporated by the radiant heat of the refrigerant flowing through theradiator 14. It is to be noted that in the present embodiment, it hasbeen described that the other end of the wick 75 abuts on the radiator14 to open, or opens in the vicinity of the radiator 14. In a case wherethe other end of the wick 75 abuts on the radiator 14 to open as in theformer case, the drainage from the other end of the wick 75 can permeatethe surface of the radiator 14 from an abutment portion. In consequence,the drainage received in the grove 70 can smoothly be discharged to theradiator 14, and evaporation can be promoted.

As described above in detail, according to the present invention, thedrainage from the evaporator 18 can securely be discharged from the duct50 regardless of the posture change of the main body 1, so that adisadvantage that the drainage flows through the optical element 5 canbe avoided in advance. In consequence, reliability of the liquid crystaldisplay projector P can be improved.

It is to be noted that in the present embodiment, the whole periphery ofthe sealed path 50A of the duct 50 which surrounds the evaporator 18 hasthe tapered shape including the center thereof outside, and the grove 70is formed in the center. However, the present invention is not limitedto this grove 70. The present invention is effective as long as theliquid receiving portion is constituted in the whole region under theevaporator 18 in the prospective posture change of the main body. Forexample, instead of the grove 70, the wick may be attached under theevaporator 18 in the prospective posture change of the main body. Inthis case, the drainage which has flowed inwards from one end is guidedto the discharge member by use of the capillary force of the wick,whereby a similar water discharge effect can be obtained. Moreover, thedischarge member is not limited to the wick 75 of the presentembodiment, and the member may be constituted of, for example, a waterabsorbing fiber. In this case, the drainage received in the liquidreceiving portion (the grove 70 in the embodiment) constituted of themoisture absorbing fiber can be discharged from the duct 50 by use ofthe permeation force.

Moreover, in the present embodiment, as one embodiment of the apparatusincluding the freezing unit 10, the liquid crystal display projector Phas been described, but the projector is not limited to this example.There is not any special restriction as long as a main body of theprojector is constituted of a light source, an optical element forprocessing the light from the light source in accordance with imageinformation, and a projection lens for projecting the processed image ofthe projected light onto a screen. For example, the present invention iseffectively applied to, for example, DLP projector (DLP (registeredtrademark)). Furthermore, in a first aspect of the invention, theapparatus including the freezing unit 10 is not limited to theprojector, and the invention may be applied to an apparatus such as aconveyable refrigerator or freezer, a car air conditioner, or a personalcomputer.

1. An apparatus including a freezing unit in which a main body isprovided with the freezing unit having a refrigerant circuit constitutedof at least a compressor, a radiator, a pressure reducing unit and anevaporator, the apparatus comprising: a liquid receiving portionconstituted in the whole region under the evaporator in a prospectiveposture change of the main body; and a discharge member which dischargesdrainage received in the liquid receiving portion by use of a capillaryforce or a permeation force.
 2. The apparatus including the freezingunit according to claim 1, wherein the discharge member discharges, tothe radiator, the drainage received in the liquid receiving portion. 3.A projector including a freezing unit, which is the apparatus accordingto claim 1 or 2, comprising a main body including a light source, anoptical element which processes light emitted from the light source inaccordance with image information, a projection lens which projects aprojected image of the processed light onto a screen, and a duct inwhich an evaporator is incorporated and which supplies, to the opticalelement, air subjected to heat exchange between the air and theevaporator, wherein the liquid receiving portion is constituted in aninner surface of the duct.